THE HWS DATA LOGGER AND HYDROLOGICAL FIELD STUDIES

The HWS Data Logger System is a small, inexpensive, microprocessor-based device that detects, digitizes, and stores up to 4000 voltages from a sensor as an 8-bit integer. The logger sample period can be preset during initialization. Recent laboratory and field tests are presented that are designed to test the accuracy, precision and suitability of this versatile system in fluvial and lacustrine settings. Circuit diagrams, part lists, manuals, circuit board layouts, interface and microchip software, and other essential items will be published shortly (http://www.hws.edu/ACA/depts/geo/Logger/logger.html) so that any educator can download this information and build her/his own data logger to use for K-12 and college level educational and/or research pursuits

Seven subwatersheds within or near the Seneca Lake Watershed of central New York were monitored during the spring and summer of 2000. Stream stage was detected every 10-minutes by data logger; and discharge and hydrochemical data was measured once a week. The Data Logger records accurate data, if deployed properly. Stage and discharge are strongly correlated but the relationship is different between streams, and the relationship relates to landuse, subwatershed area, and other variability. Coupled with the major ion, nutrient and selected pesticide data, the Data Logger provides input for hydrochemical models.

Two data loggers were deployed in North Pond, eastern Lake Ontario, from May 1 to November 10, 2000 to test the accuracy and precision of the data logger system, and determine factors that influence lake level in this aquatic setting. Both loggers simultaneously recorded lake-level every 10-minutes. Water level and meteorological data were also collected at the field site on a daily basis. The data were consistent with each other and with independently measured long-term variability. Daily and shorter, cm-scale, variability is detected may reflect storm runoff events, surface seiche and perhaps lunar-tides. This detected variability in lake-level significantly impacts current velocities and erosion of sand in the channel between North Pond and Lake Ontario.